500efi Rough Idle @ Warm
#21
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#22
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When you say the tach was jumping, was it representing RPM changes or just random jumping around? If the later, my money is on the ign sys. I'd swap distributors and test. Not sure if your engs have ign boxes or not. If so swap them first.
#23
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From: taxachusetts
stick some rubber hose on the water dumps,,extend them and see if it cleans up the skip.
#24
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there are 4 items left on ignition system to check IMO...distributor coil, ignition module, spark plugs, and ignition coil.
#25
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i seriously hope hope the brand new valve train we just put in isn’t messed up already.
#27
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Pulled one side of plugs...no sign of water or rust. Plugs do look a little lean. Going to replace them all. I would think this rules out reversion. If it were reversion there would be serious signs of water. We do run in salt water.
#28
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Pulled all plugs and replaced. Still missing and skipping. Tried swapping ignition coil still an issue. We had computer hooked up. Originally said manifold air temp sensor issue. Swapped it. Still missing. Cleared all codes. Still missing.
the spark advance was all all over the place when it was running...trying to compensate for idle. New IAC didn’t do anything.
the spark advance was all all over the place when it was running...trying to compensate for idle. New IAC didn’t do anything.




